1. Field of Invention
The present invention relates to a drive IC for driving a liquid crystal, a liquid crystal panel, a liquid crystal device formed by installing a liquid crystal drive IC on a liquid crystal panel, and an electronic apparatus having the liquid crystal device.
2. Description of Related Art
In recent years, liquid crystal devices have come to be used widely as the visual information displays for various types of electronic apparatuses such as portable telephones, digital still cameras, video cameras, and others. When a liquid crystal device is used in a portable telephone, the liquid crystal device is used for displaying such information as a telephone number, and the like. Also, when a liquid crystal device is used in a digital still camera or a video camera, the liquid crystal device is commonly used as a finder for confirming the object.
A liquid crystal device generally is formed by implementing a drive IC on the liquid crystal panel. In particular, in a portable information terminal represented by a portable telephone, it is common to be driven by a single low-cost and low-consumption drive IC, being a so-called single-chip IC. Furthermore, most recently, liquid crystal devices constructed by mounting a drive IC directly on the liquid crystal panel itself, being so-called COG (chip on glass) type liquid crystal devices, are becoming more widespread.
With these COG type liquid crystal devices, the drive IC is affixed directly on a transparent substrate of the liquid crystal panel. Also, the electrode terminals provided on the drive IC, namely the bumps or pads, and the electrodes formed on the transparent substrate are connected electrically, being so-called conductively connected. The drive IC 51 as shown in FIG. 8 generally has signal electrode terminals Bsi that conductively connect the signal electrodes Psi on the liquid crystal panel side, and scan electrode terminals Bso that conductively connect the scan electrodes Pso on the liquid crystal panel side. Also, with the conventional drive IC 51, both the signal electrode terminals Bsi and the scan electrode terminals Bso were adjacent at the identical pitch of the pitch among the signal electrode terminals Bsi and the pitch among the scan electrode terminals Bso. That pitch is generally 80-100 .mu.m.
In an ordinary liquid crystal device manufacturing process, in order to test whether or not the liquid crystal panel has the expected display properties, it is common that the liquid crystal panel be tested as a unit by printing a fixed voltage to the signal electrodes Psi and the scan electrodes Pso of the liquid crystal panel before installing the drive IC on the liquid crystal panel. Also, when printing the fixed voltage in this manner, a signal electrode conductive member 53si is contacted to the signal electrodes Psi, a scan electrode conductive member 53so is contacted to the scan electrodes Pso, and the fixed voltage is printed to each electrode Psi and Pso by a display test circuit 52 via the conductive members 53si and 53so.
Nevertheless, when performing testing related to a liquid crystal panel having the above-mentioned conventional drive IC 51, because in the conventional drive IC 51 the signal electrode terminals Psi and the scan electrode terminals Bso were adjacent at the identical narrow pitch among their respective electrode terminals, when trying to contact the conductive members 53si and 53so variously to each electrode Psi and Pso corresponding to all the electrode terminals present at the interface of those electrode terminals, there was the risk of the test becoming impossible due to shorting by those conductive members 53si and 53so contacting each other. Also, if the gap between the signal electrode conductive member 53si and the scan electrode conductive member 53so is made wider in order to avoid shorting, there was a problem that the fixed voltage could no longer be printed in the electrode sections not having those conductive members present. Therefore, a part of the display area of the liquid crystal panel could not be displayed.
Regarding liquid crystal panels using a conventional drive IC in this manner, when there were defects in parts of the liquid crystal panels corresponding to the electrode sections in which the conductive members 53si and 53so could not contact, there was a problem that the defects could not be discovered. As a result, yields decreased due to defects remaining regarding the finally obtained liquid crystal panels, and cost increases were caused thereby.